PURPOSE To identify those metallothionein and alpha-crystallin/small heat-shock genes induced by toxic metals in human lens cells and to evaluate the levels of these metals between young and aged human lenses. METHODS Human SRA01/04 and primary human lens epithelial cells were cultured and exposed to Cd(2+), Cu(2+), and Zn(2+). The levels of lens metallothioneins (Ig, If, Ih, Ie, and IIa) and...

Using the differential PCR display method to select cDNA fragments that are differentially expressed after hepatic stellate cell (HSC) activation, we have isolated from activated HSCs a cDNA that corresponds to rat alphaB-crystallin. Northern blots confirmed expression of alphaB-crystallin in culture-activated HSCs but not in quiescent HSCs. Western blot analysis and immunocytochemical staining...

α-Crystallin is a member of the small heat-shock protein (sHSP) family and consists of two subunits, αA and αB. Both αA- and αB-crystallin act as chaperones and anti-apoptotic proteins. Previous studies have identified the peptide (70)KFVIFLDVKHFSPEDLTVK(88) in αA-crystallin and the peptide (73)DRFSVNLDVKHFSPEELKVK(92) in αB-crystallin as mini-chaperones. In the human lens, lysine 70 (Lys(70)) ...

α-Crystallin, a small heat shock protein (sHSP), constitutes the major portion of eye lens cytoplasm and its concentration in the lens can reach up to 50% of the total protein. Like other sHSP, α-crystallin displays chaperone-like activity in suppressing the aggregation of various proteins and in preventing inactivation of enzymes due to heat and other stress conditions [1-6]. Hence, in additio...

PURPOSE The purpose of the study was to determine whether the autodegradation of human βA3-crystallin is due to its intrinsic protease activity. METHODS Recombinant His-tagged human βA3-crystallin was expressed in E. coli and purified by a Ni+2-affinity column chromatographic method. To determine protease activity, the purified crystallin was incubated for 24 h with either sodium deoxycholate...

The vertebrate lens is composed of two distinct cell types, the epithelial cells and the fiber cells. The absolute rate of synthesis of total protein and of purified cr-crystallin, a structural polymeric protein found in both cell types, has been calculated using the kinetics of [3H]leucine incorporation into organ-cultured lenses. The data show that in adult epithelial cells about 2% of Lu-cry...

PURPOSE Lens alpha-crystallins, composed of two subunits of alphaA- and alphaB-crystallin, form low molecular weight (LMW) water soluble aggregates with an average molecular mass of approximately 800 kDa. In the intact lens, some of the alpha-crystallins are associated with even larger high-molecular-weight (HMW) aggregates which are thought to be precursors of components found in the water ins...

m a-Crystallins were demonsl:rated recently to be involved fin interaction with a short element of the sense strand of the murine yDE/F-ctystallin genes immediately downstresm of the transcriptional initiation site @OTIS). The aim of the study was to demonstrate a consensus sequence and to test, if the interaction with a-crystallin is dependent on phospholylation. M&&& 3*P-labelled oligonucleot...

The cis-elements responsible for the high-level, lens-specific expression of the chicken beta B1-crystallin gene were investigated by generating mice harboring beta B1-crystallin promoter/chloramphenicol acetyl transferase (CAT) transgenes. Deletion of promoter sequences -434/-153 and -152/-127 as well as site-directed mutagenesis of the PL1 (-116/-102) and Pl2 (-90/-76) elements significantly ...

S-Crystallin is a major protein present in the lenses of cephalopods (octopus and squid). To facilitate the cloning of this crystallin gene, cDNA was constructed from the poly(A)+ mRNA of octopus lenses, and amplified by PCR for nucleotide sequencing. Sequencing of 10 of 15 positive clones coding for this crystallin revealed three distinct S-crystallin isoforms with 61-64% identity in nucleotid...